Cell phones during a typical week will only need a quick wipe down with a dry cloth, or with a baby wipe. If a spill happens, turn off your phone, take out the battery, and use a soft cleaning cloth with a little isopropyl alcohol as your first line of defense. For sticky spills that stick in crevices, turn off your phone, and try a cotton swab dipped in isopropyl alcohol rubbed around the button surfaces and crevices.
And although I recommend it as a complete last resort with the understanding that it may be ruined forever, I was once successful at resurrecting a cell phone that had been washed and dried, by pouring isopropyl alcohol over it after I had taken it apart and letting it dry out completely.
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